Effect of Seasonal Change and Different Commercial Feeds on Proximate Composition of Sea Bream (Sparus aurata)

Abstract

The effects of seasonal change and commercial feeds used in Aegean Sea fish farms were investigated on major quality parameters, such as condition factor, viscerosomatic index, hepatosomatic index, visceral lipid, liver lipid and fillet composition in sea bream, Sparus aurata (349.2 g average body weight). The crude protein levels in the feeds A (pelleted), B (extruded), C (pelleted) and D (extruded) were similar (45%) (P>0.05), and lipid content in extruded feeds were significantly higher (20.5%) than pelleted feeds (13.3%) (P 0.05). The fillet lipid content, lipid deposition in liver, total lipid level in visceral organs (without liver), the hepatosomatic index and viscerosomatic index of the fish fed the extruded feeds were significantly higher (P 0.05) between the crude protein levels in the fillet of the cultured and wild sea bream in summer. There were significant differences (P<0.05) in the fillet of cultured fish groups. Finally, the proximate compositions in the commercial feeds used in the sea farms of the Aegean region were found sufficient for sea bream. Furthermore, the higher fat level in the extruded feeds did not show negative effects on the proximate composition of the fish fillet.